♫ Audio Article: Download a free audio version of this article with commentary, or subscribe in iTunes!A few weeks ago I wrote up a critique of The Perfect Health Diet by Dr. Paul Jaminet and his wife, Dr. Shou Ching.
Dr. Jaminet wrote a response to my assertion that liver glycogen was an important factor in resisting stress, and followed up the original post with another on the supposed follies of sugar consumption.
In the article, Dr. Jaminet agreed that carbohydrate intake is critical for the synthesis of the active thyroid hormone, triiodothyronine (T3), however, Dr. Jaminet is not under the impression that thyroid, or any hormone for that matter, should be the focus of a diet for perfect health:

"...In any case I don’t normally discuss hormonal biology because it is too complicated and doesn’t normally provide much insight into what we should do."

Peat views thyroid as an integral part in the cell's ability to produce energy as well as maintain optimal health:

“Thyroid hormone is necessary for respiration on the cellular level, and makes possible all higher biological functions. Without the metabolic efficiency, which is promoted by thyroid hormone, life couldn’t get much beyond the single-cell stage.

Without adequate thyroid, we become sluggish, clumsy, cold, anemic, and subject to infections, heart disease, headaches, cancer, and many other diseases, and seem to be prematurely aged, because none of our tissues can function normally." - Ray Peat

Active thyroid hormone allows for an oxidative metabolism (the metabolism of our youth). In short, an oxidative metabolism creates a lot of ATP, utilizes oxygen properly, and produces boatloads of CO2.
Peat's work suggests that the ability of the cell to produce energy and utilize oxygen (CO2) is the greatest factor in promoting longevity and avoiding degeneration.

"Many other diseases are now known to be caused by respiratory defects. Inflammation, stress, immunodeficiency, autoimmunity, developmental and degenerative diseases, and aging, all involve significantly abnormal oxidative processes. Just brief oxygen deprivation triggers processes that lead to lipid peroxidation, producing a chain of other oxidative reactions when oxygen is restored."

If a reduction in thyroid performance coincides with a decrease in cellular energy, this may explain the extremely broad, beneficial actions of thyroid supplementation (Barnes).Sugar Increases Adrenaline?

Paul did note something quite strange in his article about sugar and its "stressful effects." Paul mentions that in an experiment sucrose lead to increased elevations of adrenaline:

"We can see the stressfulness of sucrose by its effects on the “fight-or-flight” stress hormones adrenaline (epinephrine) and noradrenaline (norepinephrine). Here is a study that fed high-fat, high-starch, and high-sucrose diets for 14 days to healthy non-obese subjects, and measured the hormonal response."

Paul continues to suggest that Peat has been running on adrenaline for the last several decades:

"One of the effects of adrenaline and noradrenaline is to speed up the pulse rate. If Peat really does eat 400 g of carbs per day, predominantly from sucrose, then he may be achieving his high pulse rate from an “adrenaline rush” that helps dispose of an excess of fructose.

If, indeed, this is a source of improved sense of well-being on Peat-style diets, it may be a double-edged sword. Chronic stimulation of the “fight-or-flight” hormones to aid in fructose disposal may have long-run negative consequences."

If Peat were achieving his high pulse with high levels of adrenaline, it would suggest, A) that he truly has no idea what he's doing, and 2) that his followers would also feel the negative effects of elevated adrenaline (cold hands and feet, cold nose, poor sleep, anxiety). I don't experience this; perhaps some other followers of Peat can leave some thoughts in the comments.

While studies are fun to deconstruct, the results of the experiment don't align with the basic physiology that Peat subscribes to:

"As soon as something interferes with the oxidative production of energy (not having enough oxygen, for example, as when running) we adapt biochemically first by increasing the consumption of glucose for glycolytic energy production. This increased consumption of glucose tends to lower the concentration of glucose in the blood, and this (or various other signals, such as pain or fear, that are associated with the need for more glucose) causes the secretion of adrenalin, which can mobilize glucose from the liver's glycogen stores. If the glucose stores are depleted, the body resorts to the secretion of cortisol, to provide glucose (and other material) by cannibalizing protein from tissues which are momentarily less essential."

This may be a solid reason to rely on personal labs and self-diagnostics instead of interpretations of various studies.